Abstract: Lithium-ion batteries generate huge amount of heat during charging and discharging. The accumulated heat usually leads to high battery working temperatures and big working temperature differences and thus lowers the capacity and lifespans of batteries. Even worse, it may cause fire and explosions of batteries. To reduce the working temperature and temperature difference of the battery pack, the spoiler structure is designed in the spider web channel, and the heat dissipation of cooling lithium-ion batteries is calculated by numerical methods. First, the heat dissipation of lithium-ion batteries with vertical and staggered arrangement of spoilers in spider web channel is compared, and then the impact of spoiler diameter, height, spacing and flow rate on battery cooling heat dissipation is analyzed. The results show the maximum temperature and temperature difference of the cooling battery with staggered arrangement of spoilers are markedly lower than those with vertical arrangement, and the temperature distribution of the battery module is more uniform. When the diameter of the spoiler increases to 6 mm, the batteries record the lowest maximum temperature and temperature difference, and the cooling hydraulic drop increases slightly. When the height of the spoiler increases from 0.5 mm to 2 mm, the maximum temperature and temperature difference of the batteries experience a shallow V-shaped change, and the cooling hydraulic drop increases slightly. With the increase of spoiler spacing from 6 mm to 15 mm, the maximum temperature and temperature difference of the batteries only increase slightly whereas the cooling hydraulic drop decreases significantly. The spoiler channel can meet the cooling and heat dissipation requirements of the batteries when the flow rate is 0.04 kg/s. When the structural parameters of spoilers are properly adjusted, the maximum temperature and temperature difference of the batteries are as low as 30.64 ℃ and 3.62 ℃ respectively, and the cooling hydraulic pressure drops by 1, 778.23 Pa.